The present invention relates to a spring. manufacturing apparatus and, more particularly, to a spring manufacturing apparatus for manufacturing a spring which compresses or expands in the axial direction thereof.
In a spring manufacturing apparatus, when manufacturing of a single spring is completed, the wire material is cut at the end portion of the manufactured spring.
Generally, to cut the wire material, a cutter tool is forced in the wire material at the end portion of the spring. The cutting operation is repeated every time one spring is formed.
This spring manufacturing has a problem in a case where the wire material is comparatively thick with respect to the diameter of the spring.
When the wire material is comparatively thin with respect to the diameter of the spring, the end surface (the circular cross section of the spring horizontal to the axial direction) is approximately flat. However, if the wire material is thick, the end surface of the spring is not level as shown in FIG. 7 (70). In this case, if the spring end surface is required to be flat, the wire material of the end surface is ground as shown in FIG. 7 (71). In this manner, the conventional spring manufacturing includes a spring forming process and an end surface grinding process which should be performed independently.
The end surface grinding process may be performed on both ends of a spring, further, processing time is not negligible.